The present disclosure relates to a cleaner for collecting pollutant particles such as dust and dirt and a method for driving the cleaner.
A cleaner makes it possible to clean a desired region without scattering pollutant particles such as dust and dirt. The reason for this is that the cleaner collects (or traps) pollutant particles by inhalation. In order to collect pollutant particles, the cleaner has a collecting fan that is rotated by an electric motor.
An AC voltage of about 110 V or 220 V is used to drive the electric motor of the cleaner. Thus, the cleaner is equipped with a power cord for receiving the AC voltage. This power cord, however, restricts a possible cleaning region that can be cleaned using the cleaner.
In order to overcome the restriction of the possible cleaning region, an AC/DC hybrid cleaner has been proposed that can collect pollutant particles by a DC voltage of a battery as well as by the AC voltage. The AC/DC hybrid cleaner drives an electric motor by the DC battery voltage in a region outside a radius of the length of a power cord, thereby making it possible to collect pollutant particles without the restriction of a possible clean region. While the AC/DC hybrid cleaner can obtain a DC voltage of about 310 V from the AC voltage, it can obtain a DC voltage of about 30 V from the battery. Such a difference of 10 times in the DC voltage leads to a difference of 100 times in motive power supplied to the collecting fan.
In order to minimize such a power difference caused by the DC voltage difference, the AC/DC hybrid cleaner has a hybrid universal motor with a dual-coil structure that enables a switch between a low-impedance mode and a high-impedance mode. When a 310 V DC voltage is supplied using the AC voltage, the hybrid universal motor is driven in a high-resistance mode where dual coils are connected in series to each other. On the other hand, when a DC voltage of about 30 V is supplied from the battery, the hybrid universal motor is driven in a low-resistance mode where the dual coils are connected in parallel to each other.
However, even by an impedance change due to a change in the connection structure of the dual lines, it is difficult to eliminate the difference between the power generated using the AC voltage and the power generated using the voltage of the battery. In actuality, the impedance characteristics of the dual coils of the hybrid universal motor is set to generate a rotational force (or a rotation speed) that is required in the high-resistance mode where the AC voltage is used. Therefore, in the low-resistance mode where the voltage of the battery is used, the hybrid universal motor generates only ¼ to ⅓ of the rotational force generated in the high-resistance mode where the AC voltage is used. Consequently, in the low-resistance mode where the voltage of the battery is used, the AC/DC hybrid cleaner including the hybrid universal motor has the poor capability of collecting pollutant particles and requires a long cleaning time.
Furthermore, the dual-coil structure increases the size of the hybrid universal motor by 50% or more. This increases the size of the AC/DC hybrid cleaner having the hybrid universal motor.